Studies on vector screening for Setaria cervi microfilaria

Various haemophagous arthropods including 9 species of mosquitoes, 3 species of flies and 2 species of ticks were screened in the laboratory to determine their relative potential as vector for the transmission of Stearia cervi. Colonies of vectors were maintained in the laboratory to provide an abundant supply for inducing infection to trace the development of microfilaria. Development of microfilaria up to the infective stage occurred only in mosquitoes Aedes albopictus, A. aegypti (NICD laboratory strain) and A. aegypti (wild strain), though the rate of development varied among them. All the remaining vectors were either refractory or inefficient to support the development of microfilaria. Defence reactions against this worm were also reported in the inefficient mosquito host. Aedes scatophagoides and in the susceptible mosquito host, A. aegypti (wild strain). This work provides a better understanding of possible intermediate hosts of Setaria cervi and at the same time rules out the possibility of many of the arthropods earlier presumed to be vectors of this parasite. (Other species mentioned in this study are Culex fatigans, C. vishnui, C. fuscans, Anopheles subpictus, A. stephensi, Armigeres obturbans, Stomoxys calcitrans, Tabanus brunnipennis, Hippobosca maculata, Haemaphysalis bispinosa and Boophilus microplus.)